From 78d9d8005e4556448f398d876f29d0ca7ab8e398 Mon Sep 17 00:00:00 2001 From: Jisheng Zhang Date: Fri, 16 Jul 2021 21:40:51 +0800 Subject: riscv: stacktrace: Fix NULL pointer dereference When CONFIG_FRAME_POINTER=y, calling dump_stack() can always trigger NULL pointer dereference panic similar as below: [ 0.396060] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc5+ #47 [ 0.396692] Hardware name: riscv-virtio,qemu (DT) [ 0.397176] Call Trace: [ 0.398191] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000960 [ 0.399487] Oops [#1] [ 0.399739] Modules linked in: [ 0.400135] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.13.0-rc5+ #47 [ 0.400570] Hardware name: riscv-virtio,qemu (DT) [ 0.400926] epc : walk_stackframe+0xc4/0xdc [ 0.401291] ra : dump_backtrace+0x30/0x38 [ 0.401630] epc : ffffffff80004922 ra : ffffffff8000496a sp : ffffffe000f3bd00 [ 0.402115] gp : ffffffff80cfdcb8 tp : ffffffe000f30000 t0 : ffffffff80d0b0cf [ 0.402602] t1 : ffffffff80d0b0c0 t2 : 0000000000000000 s0 : ffffffe000f3bd60 [ 0.403071] s1 : ffffffff808bc2e8 a0 : 0000000000001000 a1 : 0000000000000000 [ 0.403448] a2 : ffffffff803d7088 a3 : ffffffff808bc2e8 a4 : 6131725dbc24d400 [ 0.403820] a5 : 0000000000001000 a6 : 0000000000000002 a7 : ffffffffffffffff [ 0.404226] s2 : 0000000000000000 s3 : 0000000000000000 s4 : 0000000000000000 [ 0.404634] s5 : ffffffff803d7088 s6 : ffffffff808bc2e8 s7 : ffffffff80630650 [ 0.405085] s8 : ffffffff80912a80 s9 : 0000000000000008 s10: ffffffff804000fc [ 0.405388] s11: 0000000000000000 t3 : 0000000000000043 t4 : ffffffffffffffff [ 0.405616] t5 : 000000000000003d t6 : ffffffe000f3baa8 [ 0.405793] status: 0000000000000100 badaddr: 0000000000000960 cause: 000000000000000d [ 0.406135] [] walk_stackframe+0xc4/0xdc [ 0.407032] [] dump_backtrace+0x30/0x38 [ 0.407797] [] show_stack+0x40/0x4c [ 0.408234] [] dump_stack+0x90/0xb6 [ 0.409019] [] ptdump_init+0x20/0xc4 [ 0.409681] [] do_one_initcall+0x4c/0x226 [ 0.410110] [] kernel_init_freeable+0x1f4/0x258 [ 0.410562] [] kernel_init+0x22/0x148 [ 0.410959] [] ret_from_exception+0x0/0x14 [ 0.412241] ---[ end trace b2ab92c901b96251 ]--- [ 0.413099] Kernel panic - not syncing: Attempted to kill init! exitcode=0x0000000b The reason is the task is NULL when we finally call walk_stackframe() the NULL is passed from __dump_stack(): |static void __dump_stack(void) |{ | dump_stack_print_info(KERN_DEFAULT); | show_stack(NULL, NULL, KERN_DEFAULT); |} Fix this issue by checking "task == NULL" case in walk_stackframe(). Fixes: eac2f3059e02 ("riscv: stacktrace: fix the riscv stacktrace when CONFIG_FRAME_POINTER enabled") Signed-off-by: Jisheng Zhang Reviewed-by: Atish Patra Tested-by: Wende Tan Signed-off-by: Palmer Dabbelt --- arch/riscv/kernel/stacktrace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/riscv/kernel/stacktrace.c b/arch/riscv/kernel/stacktrace.c index ac7593607fa6..315db3d0229b 100644 --- a/arch/riscv/kernel/stacktrace.c +++ b/arch/riscv/kernel/stacktrace.c @@ -27,7 +27,7 @@ void notrace walk_stackframe(struct task_struct *task, struct pt_regs *regs, fp = frame_pointer(regs); sp = user_stack_pointer(regs); pc = instruction_pointer(regs); - } else if (task == current) { + } else if (task == NULL || task == current) { fp = (unsigned long)__builtin_frame_address(1); sp = (unsigned long)__builtin_frame_address(0); pc = (unsigned long)__builtin_return_address(0); -- cgit From d09560435cb712c9ec1e62b8a43a79b0af69fe77 Mon Sep 17 00:00:00 2001 From: Qiu Wenbo Date: Sun, 4 Jul 2021 16:34:41 +0800 Subject: riscv: dts: fix memory size for the SiFive HiFive Unmatched The production version of HiFive Unmatched have 16GB memory. Signed-off-by: Qiu Wenbo Signed-off-by: Palmer Dabbelt --- arch/riscv/boot/dts/sifive/hifive-unmatched-a00.dts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/riscv/boot/dts/sifive/hifive-unmatched-a00.dts b/arch/riscv/boot/dts/sifive/hifive-unmatched-a00.dts index b1c3c596578f..2e4ea84f27e7 100644 --- a/arch/riscv/boot/dts/sifive/hifive-unmatched-a00.dts +++ b/arch/riscv/boot/dts/sifive/hifive-unmatched-a00.dts @@ -24,7 +24,7 @@ memory@80000000 { device_type = "memory"; - reg = <0x0 0x80000000 0x2 0x00000000>; + reg = <0x0 0x80000000 0x4 0x00000000>; }; soc { -- cgit From a18b14d8886614b3c7d290c4cfc33389822b0535 Mon Sep 17 00:00:00 2001 From: Guenter Roeck Date: Tue, 6 Jul 2021 09:26:21 -0700 Subject: riscv: Disable STACKPROTECTOR_PER_TASK if GCC_PLUGIN_RANDSTRUCT is enabled riscv uses the value of TSK_STACK_CANARY to set stack-protector-guard-offset. With GCC_PLUGIN_RANDSTRUCT enabled, that value is non-deterministic, and with riscv:allmodconfig often results in build errors such as cc1: error: '8120' is not a valid offset in '-mstack-protector-guard-offset=' Enable STACKPROTECTOR_PER_TASK only if GCC_PLUGIN_RANDSTRUCT is disabled to fix the problem. Fixes: fea2fed201ee5 ("riscv: Enable per-task stack canaries") Signed-off-by: Guenter Roeck Signed-off-by: Palmer Dabbelt --- arch/riscv/Kconfig | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 8fcceb8eda07..31f9e92f1402 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -492,6 +492,7 @@ config CC_HAVE_STACKPROTECTOR_TLS config STACKPROTECTOR_PER_TASK def_bool y + depends on !GCC_PLUGIN_RANDSTRUCT depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS config PHYS_RAM_BASE -- cgit From 6d7f91d914bc90a15ebc426440c26081337ceaa1 Mon Sep 17 00:00:00 2001 From: Alexandre Ghiti Date: Wed, 21 Jul 2021 09:59:35 +0200 Subject: riscv: Get rid of CONFIG_PHYS_RAM_BASE in kernel physical address conversion The usage of CONFIG_PHYS_RAM_BASE for all kernel types was a mistake: this value is implementation-specific and this breaks the genericity of the RISC-V kernel. Fix this by introducing a new variable phys_ram_base that holds this value at runtime and use it in the kernel physical address conversion macro. Since this value is used only for XIP kernels, evaluate it only if CONFIG_XIP_KERNEL is set which in addition optimizes this macro for standard kernels at compile-time. Signed-off-by: Alexandre Ghiti Tested-by: Emil Renner Berthing Reviewed-by: Jisheng Zhang Fixes: 44c922572952 ("RISC-V: enable XIP") Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt --- arch/riscv/include/asm/page.h | 7 ++++--- arch/riscv/mm/init.c | 17 ++++++++++++----- 2 files changed, 16 insertions(+), 8 deletions(-) diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h index cca8764aed83..b0ca5058e7ae 100644 --- a/arch/riscv/include/asm/page.h +++ b/arch/riscv/include/asm/page.h @@ -103,6 +103,7 @@ struct kernel_mapping { }; extern struct kernel_mapping kernel_map; +extern phys_addr_t phys_ram_base; #ifdef CONFIG_64BIT #define is_kernel_mapping(x) \ @@ -113,9 +114,9 @@ extern struct kernel_mapping kernel_map; #define linear_mapping_pa_to_va(x) ((void *)((unsigned long)(x) + kernel_map.va_pa_offset)) #define kernel_mapping_pa_to_va(y) ({ \ unsigned long _y = y; \ - (_y >= CONFIG_PHYS_RAM_BASE) ? \ - (void *)((unsigned long)(_y) + kernel_map.va_kernel_pa_offset + XIP_OFFSET) : \ - (void *)((unsigned long)(_y) + kernel_map.va_kernel_xip_pa_offset); \ + (IS_ENABLED(CONFIG_XIP_KERNEL) && _y < phys_ram_base) ? \ + (void *)((unsigned long)(_y) + kernel_map.va_kernel_xip_pa_offset) : \ + (void *)((unsigned long)(_y) + kernel_map.va_kernel_pa_offset + XIP_OFFSET); \ }) #define __pa_to_va_nodebug(x) linear_mapping_pa_to_va(x) diff --git a/arch/riscv/mm/init.c b/arch/riscv/mm/init.c index a14bf3910eec..88134cc288d9 100644 --- a/arch/riscv/mm/init.c +++ b/arch/riscv/mm/init.c @@ -36,6 +36,9 @@ EXPORT_SYMBOL(kernel_map); #define kernel_map (*(struct kernel_mapping *)XIP_FIXUP(&kernel_map)) #endif +phys_addr_t phys_ram_base __ro_after_init; +EXPORT_SYMBOL(phys_ram_base); + #ifdef CONFIG_XIP_KERNEL extern char _xiprom[], _exiprom[]; #endif @@ -160,7 +163,7 @@ static void __init setup_bootmem(void) phys_addr_t vmlinux_end = __pa_symbol(&_end); phys_addr_t vmlinux_start = __pa_symbol(&_start); phys_addr_t __maybe_unused max_mapped_addr; - phys_addr_t dram_end; + phys_addr_t phys_ram_end; #ifdef CONFIG_XIP_KERNEL vmlinux_start = __pa_symbol(&_sdata); @@ -181,9 +184,12 @@ static void __init setup_bootmem(void) #endif memblock_reserve(vmlinux_start, vmlinux_end - vmlinux_start); - dram_end = memblock_end_of_DRAM(); + phys_ram_end = memblock_end_of_DRAM(); #ifndef CONFIG_64BIT +#ifndef CONFIG_XIP_KERNEL + phys_ram_base = memblock_start_of_DRAM(); +#endif /* * memblock allocator is not aware of the fact that last 4K bytes of * the addressable memory can not be mapped because of IS_ERR_VALUE @@ -194,12 +200,12 @@ static void __init setup_bootmem(void) * be done in create_kernel_page_table. */ max_mapped_addr = __pa(~(ulong)0); - if (max_mapped_addr == (dram_end - 1)) + if (max_mapped_addr == (phys_ram_end - 1)) memblock_set_current_limit(max_mapped_addr - 4096); #endif - min_low_pfn = PFN_UP(memblock_start_of_DRAM()); - max_low_pfn = max_pfn = PFN_DOWN(dram_end); + min_low_pfn = PFN_UP(phys_ram_base); + max_low_pfn = max_pfn = PFN_DOWN(phys_ram_end); dma32_phys_limit = min(4UL * SZ_1G, (unsigned long)PFN_PHYS(max_low_pfn)); set_max_mapnr(max_low_pfn - ARCH_PFN_OFFSET); @@ -558,6 +564,7 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa) kernel_map.xiprom = (uintptr_t)CONFIG_XIP_PHYS_ADDR; kernel_map.xiprom_sz = (uintptr_t)(&_exiprom) - (uintptr_t)(&_xiprom); + phys_ram_base = CONFIG_PHYS_RAM_BASE; kernel_map.phys_addr = (uintptr_t)CONFIG_PHYS_RAM_BASE; kernel_map.size = (uintptr_t)(&_end) - (uintptr_t)(&_sdata); -- cgit From 867432bec1c6e7df21a361d7f12022a8c5f54022 Mon Sep 17 00:00:00 2001 From: Alexandre Ghiti Date: Wed, 21 Jul 2021 09:59:36 +0200 Subject: Revert "riscv: Remove CONFIG_PHYS_RAM_BASE_FIXED" This reverts commit 9b79878ced8f7ab85c57623f8b1f6882e484a316. The removal of this config exposes CONFIG_PHYS_RAM_BASE for all kernel types: this value being implementation-specific, this breaks the genericity of the RISC-V kernel so revert it. Signed-off-by: Alexandre Ghiti Tested-by: Emil Renner Berthing Reviewed-by: Jisheng Zhang Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt --- arch/riscv/Kconfig | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 31f9e92f1402..4f7b70ae7c31 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -495,8 +495,13 @@ config STACKPROTECTOR_PER_TASK depends on !GCC_PLUGIN_RANDSTRUCT depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_TLS +config PHYS_RAM_BASE_FIXED + bool "Explicitly specified physical RAM address" + default n + config PHYS_RAM_BASE hex "Platform Physical RAM address" + depends on PHYS_RAM_BASE_FIXED default "0x80000000" help This is the physical address of RAM in the system. It has to be @@ -509,6 +514,7 @@ config XIP_KERNEL # This prevents XIP from being enabled by all{yes,mod}config, which # fail to build since XIP doesn't support large kernels. depends on !COMPILE_TEST + select PHYS_RAM_BASE_FIXED help Execute-In-Place allows the kernel to run from non-volatile storage directly addressable by the CPU, such as NOR flash. This saves RAM -- cgit